Electronic systems inside of cleanrooms, especially power electronics systems, pose a contamination problem if any electronic components malfunction and begin to generate smoke or other undesirable aerosols or particles. If this smoke is able to leave the enclosure and contaminate the cleanroom (or other environment where low aerosol and/or particle count is preferred), the cleanroom may have to be shut down and cleaned—a process that can cost tens or hundreds of thousands of dollars in lost output.
It is possible to make completely enclosed electrical enclosures that could prevent smoke, if generated, from escaping into the cleanroom or other environment. However, such enclosures are difficult and expensive to make, and would require more complicated and expensive cooling systems. The simplicity and lack of expense for systems that cool electronics within an enclosure via exhausting warm/hot air into the cleanroom are preferred, and therefore there is a need to detect smoke generated from an electronics enclosure that vents.
Although smoke and other aerosol/particle detectors exist, a further challenge is that electronics within an electronics enclosure are sometimes isolated or partitioned such that zero or near-zero airflow between compartments exists. For instance, components such as an RF power amplifier and a control-board or motherboard are often isolated in separate compartments of an electronics enclosure used to power plasma processing tools. Use of a single smoke or aerosol/particle detector is hampered by this lack of airflow between compartments, and therefore unable to quickly detect smoke in other compartments.
This challenge is further complicated by the fact that system fans, and other cooling means, are often used to rapidly remove warm/hot air from the compartments into the external atmosphere. Thus, smoke escapes the enclosure faster than it moves between compartments, if at all. There is therefore a need for rapid smoke detection in any of the one or more compartments.
A possible solution is to locate a sensor in each of the compartments. However, due to limited space within such enclosures, as well as cost and complexity concerns, use of multiple sensors is not desirable. There is therefore a need for a smoke detection means that rapidly detects smoke generated in any one or more compartments of a multi-compartment electronics enclosure and does not take up excessive space.